A bunion, or hallux valgus, is the tilting of the toe away from the mid-line of the foot. FIG. 1 illustrates a bunion 5 as formed on one of a pair of feet. While bunions 5 can theoretically occur in any toe, they typically occur in the big toe 7 and only very occasionally in the little toe. Hallux valgus (although strictly referring to the big toe 7, the term xe2x80x98hallux valgusxe2x80x99 is used herein to generally refer to the bunion condition) is typically characterized by a lump or bump that is red, swollen and/or painful on the inside of the foot in and around the affected toe joint 9. xe2x80x98Hallux valgusxe2x80x99 literally describes what happens to the big toe 7. Hallux is the medical term for xe2x80x9cbig toexe2x80x9d, and valgus is an anatomic term that means the deformity goes in a direction away from the midline of the body. So, in hallux valgus, the big toe 7 begins to point towards the outside of the foot (i.e., towards and usually over- or underlapping the other toes). As this condition grows worse, other changes occur in the foot that compound the problem. As illustrated in FIGS. 2-5, the bone just above the big toe 7 (the first metatarsal) usually develops too much of an angle in the other direction. This condition is called metatarsus primus varus. Metatarsus primus means xe2x80x9cfirst metatarsalxe2x80x9d, and varus means that the deformity goes in a direction towards the midline of the body.
The joint 9 at the base of the big toe 7 is the most complex joint in the foot, comprising a pair of irregularly shaped bone or joint faces coming together to form a heavy load-bearing joint 9. Here the bones, tendons and ligaments work together to transmit and distribute the body""s weight, especially during movement. Should this joint 9 become abnormally stressed over an extended period of time, a bunion 5 deformity may result. A bunion 5 is the protuberance of bone and/or tissue around the joint 9. The tissue enlargement occurs either at the base of the big toe 7 (a traditional bunion 5) or on the outside of the foot, at the base of the little toe (commonly referred to as a xe2x80x9cbunionettexe2x80x9d or xe2x80x9ctailor""s bunionxe2x80x9d).
Bunions 5 at the base of the big toe 7 usually begin when the big toe 7 starts moving toward the smaller toes, such as when tight, pointed shoes are worn. This crowding puts pressure on the joint 9, pushing it outward. The portions of the bones intersecting at and comprising the joint 9 therefore become hyper-rotated, resulting in the joint 9 moving outwardly as a result of the stresses upon it. The movement of the joint 9 in this outward direction initiates the formation of a bunion 5 as the joined bones are no longer collinear.
A common deformity of the big toe joint 9, a bunion 5 almost always mostly among people who wear shoes. Women are more frequently affected with bunions 5 because of their preference for tight, pointed, confining or high-heeled shoes. Wearing high heels is especially stressful on the joints of the foot because all of the body""s weight rests there. The foot is then forced into a narrow, pointed xe2x80x9ctoe boxxe2x80x9d, compounding the problem. Older people are also vulnerable to bunions 5 because of the higher incidence of arthritis affecting the big toe joint 9.
Bunions 5 are primarily a hereditary condition and, once begun, generally progressively worsen throughout life. However, it must be noted that it is the foot type that is hereditary, not the bunion 5 itself. People with flat feet or low arches are more prone to develop bunions 5 than those with higher arches. Bunions 5 also may be associated with various forms of arthritis. Arthritis can cause the joint""s 9 protective covering of cartilage to deteriorate, leaving the joint 9 damaged and with a decreased range of motion.
As noted above, bunions 5 arise from mechanical instability within the foot, resulting in a misalignment of the bones therein and are typically characterized by the big toe 7 drifting either over or under the second toe. As a bunion 5 deformity progresses, a characteristic bump forms and grows behind the inside of the big toe 7. The act of walking requires the big toe 7 to support a great deal of the body""s weight and therefore actuates the progression of the bunion 5. As the bunion 5 increases in severity, the condition may be complicated by the generation of other associated foot problems, such as hammertoes, painful calluses on the bottom of the foot, arch pain and the like.
Pain from a bunion 5 can range from mild to severe, making it difficult to walk in normal shoes, especially high-heeled shoes. The skin and deeper tissues around the bunion 5 may also become swollen or inflamed. Moreover, the other toes may be affected by the bunion 5, such as by result of pressure from the big toe 7 urging the lesser toes inwardly. Further, toenails may begin to grow into the sides of the nail bed. Likewise, the smaller toes can develop corns and/or become bent (hammertoes) and/or calluses may form on the bottom of the foot.
Bunion 5 treatments vary depending on the severity of pain and deformity related to the bunion 5. When left untreated, bunions 5 tend to grow larger and, usually, more painful. One common bunion treatment is to pad the bunion 5. While effective in diminishing the pain associated with the bunion 5, padding does not address the cause of the bunion 5. Likewise, switching from poorly fitting and constrictive shoes may lessen the pain from the bunion 5, but do not reverse the bunion condition.
Likewise, medications, such as anti-inflammatory drugs or cortisone injections may be administered to ease pain and inflammation caused by joint deformities. However, such medications do not correct or reverse such ongoing joint deformities. Physical therapy, such as through ultrasound treatment, whirlpool baths or other techniques can also provide temporary relief by easing the swelling and inflammation of the surrounding tissues.
There are a number of known devices for correcting bunions 5. One such device is described in U.S. Pat. No. 353,910, issued Dec. 7, 1886 to Zacharie and incorporated herein by reference. The ""910 patent describes a leather-covered brass appliance that extends under the foot to connect the toe to the ankle. The ""910 patent teaches application of a force upon the big toe 7 that pulls the big toe 7 away from the other toes but also back into the foot. Use of the ""910 device therefore results in direct compression of the afflicted and enlarged joint 9.
U.S. Pat. No. 3,219,032, issued Nov. 23, 1965 to Levitt and incorporated herein by reference discloses a metallic bunion splint worn on the foot, engaging the big toe 7 and anchored around the heel. The ""032 splint exerts a lateral transverse force on the big toe 7, pulling it out and away from the other toes. The ""032 splint, however, does not directly address the cause of the bunion joint deformity (i.e., derotation of the joint), but instead only addresses the symptom (i.e., the misaligned toe).
Probably the most extreme treatment for bunions 5 is surgery. While pain and deformity are significantly reduced in the great majority of patients who undergo bunion surgery, bunion surgery in and its associated recovery can be both painful and costly. Moreover, the recovery period is relatively slow since the surgery involves manipulation and alteration of intricate load-bearing bones. Further, postoperative orthoses and/or supportive devices are often required to improve foot function.
Bunion surgical procedures range from removal of the enlarged portion of bone and the realignment of the muscles, tendons and ligaments surrounding the joint 9 through the cutting of the bone to facilitate a shift to its proper position (which may likewise involve moving the surrounding tendons and ligaments) to a combination of the removal of the enlarged portion of the bone; cutting and realignment of the bone; and correction of the tendons and ligaments. If the joint 9 is destroyed beyond repair (commonly seen in arthritis), it may need to be reconstructed or replaced with an artificial joint. Joint replacement implants may be used in the reconstruction of the big toe joint 9.
There exist a number of wearable devices and appliances designed to correct bunion. conditions without surgery. These tend to involve splints or like devices that pull the afflicted toe 7 away from the other toes back towards its orientation parallel to the mid-line of the foot. While useful, the known devices tend to be bulky and uncomfortable. Moreover, the known devices have not substantially eliminated the need for bunion surgery.
There therefore remains a need for a bunion correction device that is more effective in correcting bunion conditions by addressing the cause of the bunion 5 instead of merely the symptom, thereby reducing and/or eliminating the requirement for bunion corrective surgery. The present invention addresses this need.
The present invention relates to a method and apparatus for the non-surgical correction of bunion conditions. One object of the present invention is to provide an improved bunion correction appliance. Related objects and advantages of the present invention will be apparent from the following description.